The present invention relates to a semiconductor radiation detector and, more particularly, to a new and improved semiconductor radiation detector having improved radiation detection efficiency.
Our prior copending application Ser. No. 613,890, filed May 24, 1984, discloses a semiconductor radiation detector comprising a substrate of single-crystal silicon, a hydrogen-added undoped amorphous silicon film deposited on the substrate, and metal electrodes deposited on the upper and lower surfaces of the substrate coated with the amorphous silicon film.
Since the hydrogen-added undoped amorphous silicon used in that arrangement has a fixed mobility band gap, however, the size of the energy barrier in the heterojunction of the single-crystal silicon and the hydrogen-added undoped amorphous silicon is uniquely determined. This imposes a limitation on the reduction of the reverse leakage current and also on the reduction of the noise level which can be obtained in that form of semiconductor radiation detector.
Accordingly, it is an object of the present invention to provide a semiconductor radiation detector in which the reverse leakage current is reduced and the radiation detecting efficiency is increased.